JPS5885478A - Liquid crystal display element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a liquid crystal display device.

In liquid crystal display devices, for example, flat-type liquid crystal display devices that display television images, there are two types: the so-called X-Y simple matrix method, and the active matrix method that incorporates a switching MO8) transistor (insulated gate field effect transistor) and a hold capacitor. is generally known.

Among these display devices, the latter active matrix method is superior in terms of display image gradation and crosstalk. This type of active matrix type liquid crystal display device uses time division multiplex driving.

This drive circuit has a configuration shown in FIG. 1, for example. In the figure, LC indicates each liquid crystal display section arranged in a matrix in the horizontal and vertical directions. These liquid crystal display parts LC
Each of the ten thousand electrodes is made into a common electrode and is set to, for example, a ground potential, and the other electrodes are each independently derived as a picture element electrode. In the figure, (1) indicates a horizontal control circuit section including a horizontal shift register, a buffer circuit input circuit, etc., (21 indicates a vertical shift register,
A horizontal control circuit section (1) is supplied with a pregnancy display signal to a vertical direction control circuit section including a Batza circuit, etc., and sequentially switches each liquid crystal display section to display a display using a switching MUS (MUS) transistor. Further, C indicates a capacitor for charge storage, that is, a hold capacitor, during each yield signal period.

In such an active matrix type liquid crystal display device, the present invention forms the liquid crystal display section and its driving circuit on a common substrate, thereby making the entire device compact and compact, and further extending the life of the liquid crystal display section. An object of the present invention is to provide a liquid crystal display device designed to achieve the following.

1. First, an example of applying the present invention to a reflective liquid crystal display device will be explained with reference to FIGS. 2 and 3.

FIG. 2 is a schematic plan view of the device of the present invention, and FIG. 3 is an enlarged sectional view of a portion thereof. The schematic structure of the present invention device will be explained with reference to Figure 2. In the present invention, the substrate (
A liquid-tight space in which a liquid crystal (131) is sealed is formed between the Lυ and a transparent substrate (12) provided opposite thereto.Then, in the center of the liquid-tight space, a liquid crystal display section E constituting each picture element is arranged. The peripheral circuit section S constituting the control circuits (1) and (21) explained in FIG.

The substrate (Ill, for example, has 100 crystal planes and has a specific resistance of 2 to
The transparent substrate Q2+ is made of a silicon semiconductor substrate of 3 Ω·σ, and the transparent substrate Q2+ provided opposite thereto is made of, for example, quartz glass or float glass. In the liquid-tight space formed between these liquid crystals, for example, guest
A host-type liquid crystal (131) is sealed. On the substrate (II), as shown in FIG. A semiconductor circuit is provided.As mentioned above, the peripheral circuit section S that constitutes the control circuits (1) and (2) explained in FIG. A plurality of picture element parts of the display part E are arranged horizontally and vertically, that is, in a matrix along the board surface direction of the substrate Q21. For example, N-type source and drain regions (14s) correspond to these display areas.
and (14d) are formed by ion implantation, diffusion, etc., and a gate insulating layer (151, for example, 5+0
Two layers are formed, and a gate electrode a0 is further provided on this to form the switching MOS transistor described in FIG. 1. Also, these source areas (14s)
And on the drain region (14d), a conductive layer Qη is provided which is ohmically connected to serve as a source electrode and a drain electrode, respectively, and a wiring portion between these. A high concentration region (1&) of the same conductivity type as the substrate (111) is provided on the surface of the substrate (old substrate) adjacent to each of these MU8s, and on top of this, for example, a layer of 5r02 etc. formed at the same time as the gate insulating layer +151 is provided. A thin dielectric layer (1) is formed on which the MOS
A conductive layer (+7) connected to the drain electrode extends to form the capacitor 1c explained in FIG. 1 between the high concentration region and the high concentration region. The conductive layer flrI is a conductive layer such as a wiring or an electrode in the peripheral circuit section S (along with 201, for example, a low resistivity polycrystalline semiconductor layer such as a source, drain, region (14s)
It can be formed of an N-type polycrystalline silicon layer having the same conductivity type as (14d) and (14d). (21) is an insulating layer formed on the surface of the substrate 0υ, for example a thick SiU2 oxide layer. In addition, an insulating layer such as phosphor glass or arsenic glass is formed on the entire surface including the conductive layer aη and the top of the screen, and windows are bored in predetermined parts of the conductive layer (171 and (2)). A metal wiring layer, for example, an M-layer area, is formed in a predetermined pattern to connect the conductive layer aη and (terminals electrically connected to the wave or each conductive layer +17) and (a) through these layers. An insulating layer (2 m) of so-called glass-flowed phosphor glass or polyimide resin is deposited on the top so that the surface is smoothed.
231, there is an electrode for applying voltage to the liquid crystal, especially the display part E, that is, a picture element electrode (231) provided corresponding to each picture element.
4J and a portion facing the peripheral circuit portion S, in other words, a ring-shaped peripheral electrode (25) for the four circumferences of the liquid crystal (131) and a terminal portion (3) are arranged in a portion other than the original display portion. Each pixel electrode A is connected to a gold layer wiring layer (22) connected to a conductive layer αη, which serves as a part of the electrode of a capacitor C, for example, through a window drilled in an insulating layer C (231). The alignment treatment to obtain the alignment effect of liquid crystal such as 8+02 is performed on the entire surface of the electrodes (2 and (c)) and the insulating layer (2 (to)) where these are not formed. The resulting alignment layer (26) is applied over the entire surface.

- On the inner surface of the transparent substrate a2, a peripheral electrode (an electrode having a light shielding property opposite to the peripheral electrode 251 provided on the substrate fill side) is provided.
2) For example, an electrode in which a Cr layer and an Au layer are stacked or a T
An electrode is formed in which an i layer and an Al1 layer are laminated. On this electrode (5), an alignment layer (5) of 5iOz or the like which has been similarly subjected to an alignment treatment to obtain a liquid crystal alignment effect is formed. In addition, on the inner surface of the portion constituting the display section E of the transparent substrate (121), each picture element electrode (2a has a common counter electrode (29+ transparent'!I! layer, etc. This counter electrode is electrically connected to the light-shielding electrode (W) through a window formed in the alignment layer ((G), so that, for example, a ground potential is supplied to them. The surface of 29) is also subjected to an alignment treatment to obtain a liquid crystal alignment effect.

(to) is a spacer that regulates the thickness of the enclosed space of the liquid crystal 03 by regulating the distance between the substrate (lυ) and the transparent substrate (121), and a barrier that keeps the liquid crystal enclosed space liquid-tight. Or a conductor made of In bumps etc.
For example, a light-shielding electrode (2η) and a corresponding terminal portion are electrically connected.

On the back surface of the substrate (111), an electrode layer, eg, a 300× thick Il+ layer and a 3000× thick layer A, are stacked and deposited, and a ground potential is applied to this, for example.

In particular, in the present invention, a ground potential of the same potential as the peripheral electrode (251K) is applied to the liquid crystal (131K).
The liquid crystal in the peripheral circuit section other than the display section is made to be in an electric field-free state.

In a display device with such a configuration, the control circuits (1) and (2) explained in FIG. Since it is formed in an integrated manner, it is possible to achieve compactness and compactness, and also to simplify assembly and manufacturing, thereby increasing mass production. Since the same potential is applied to the electrode (25) and the light-shielding electrode (2η), no electric field is applied to this part, and this prevents fatigue of the liquid crystal here. It is possible to avoid the inconvenience that deterioration of the characteristics of the liquid crystal due to fatigue extends to other original display parts.

In the above example, the common counter electrode C2!11 in the liquid crystal display section EK is also given a ground potential and is electrically connected to the light-shielding electrode (27), but this counter electrode ( It goes without saying that if a potential different from that of the light-shielding electrode (27) is not applied to the light-shielding electrode (29), the counter electrode and the light-shielding electrode (2η) are electrically separated and the terminals are led out independently from the light-shielding electrode (27). It would be a good place.

In the above-described device of the present invention, a signal voltage corresponding to a video display signal is applied to the pixel electrode (24) of each pixel of the liquid crystal display section E by the drive control circuit provided on the substrate 01).
Next, a predetermined voltage is applied to the liquid crystal of each pixel part by cooperation with the counter electrode #i which faces the applied voltage, and this produces an optical change. Observation can be made through the opposed type 'w!+291, and the desired optical display can be obtained.

In the above example, the present invention is applied to a reflective liquid crystal display device, but the present invention can also be applied to a transmissive liquid crystal display device. An example of this case will be explained with reference to FIG. FIG. 4 shows an enlarged sectional view of the main parts of this transmission type liquid crystal display device, and parts corresponding to those in FIG. 3 are given the same reference numerals and redundant explanation will be omitted. That is, in this example as well, the substrate (11) and the transparent substrate (121) are provided facing each other in the same way as described above.Then, a liquid crystal, for example, a nematic twist type liquid crystal (
131, the central part constitutes the liquid crystal display section E constituting each picture element, and the peripheral circuit section constituting the control circuit section (11 and (2)) explained in FIG. Particularly in this example, the substrate (11) is made of a transparent substrate, such as a sapphire substrate, and a semiconductor layer (11) is formed on this sapphire substrate (III) by, for example, epitaxial growth. A semiconductor circuit similar to that explained in FIG. 3 is formed. That is, a peripheral circuit section S constituting the control circuit fi+ and (2) explained in FIG. 1 is formed in the peripheral part of this semiconductor layer (4υ), On the inner side, a plurality of picture elements of the display section E are arranged in a matrix, and a drive circuit corresponding to each picture element explained in FIG.
and C are placed.

In this example, the capacitance 'fjkC is sandwiched between a thin insulating layer (1!1) formed on a high concentration region (in this example, an N-type high concentration region) provided in the semiconductor layer (41) and the drain region ( 14d) conductive layer (I) ohmically coupled to
7) and this conductive layer σ
The capacitance formed between the electrode layer (421) made of, for example, Ta, which extends over η via the insulating layer (33) and is ohmically connected to the high concentration region f181, and this electrode layer ( 4a and its Ta surface oxidized
The capacitance formed between the gold conductive layer (221) and the gold conductive layer (221) which extends over this through an insulating layer consisting of 205 and is electrically connected to the drain region (14d) is connected in parallel. ft.

In this example, each picture element electrode (24) is formed of a transparent electrode such as 5nU2 or TlU3.

One transparent substrate (on the other side, there is a light-shielding conductive layer (43) in a lattice or net shape to separate each picture element (for example, a conductive layer of each laminated structure of Cr layer-AuN or Ti layer-AU layer). This light-shielding conductive layer (431 can be formed simultaneously with the formation of the light-shielding layer W (271) provided around the transparent substrate 112, and is further connected reciprocally, that is, electrically Transparent counter electrodes (
2. The light-shielding conductive layer (81) is deposited within the grid or mesh where 43 is not formed, as in the above example.
(Insulating layer such as J2 (2) Shading through the window drilled in the hole 1!
Sui (connected to Jun.

On the back side of the substrate IIH, a light shielding layer (for example, black silicone resin, epoxy resin, black metal, carbon A metal layer (4η) such as Ag is formed via a polycrystalline silicon layer (461) or a light shielding layer (4ω It can also be composed of these polycrystalline silicon layers (46) and metal layers (8R layers of 4η).

In this way, the light shielding layer (451) of the substrate (Ill and 02)
The inside of the lattice or mesh of (4,:l) is used as a light transmitting part, and these are used as each pixel part of display part E, and each M (JS be placed.

In such a configuration, a signal voltage corresponding to the video display signal is sequentially applied to the transparent picture element electrode of each picture element of the liquid crystal display section E by a drive control circuit provided on the substrate circle, as in the above-mentioned example. A predetermined voltage is applied to the liquid crystal of each picture element by the cooperation of this and the opposing electrode 3, and as is well known, the optical rotation is controlled and the transmitted light is transmitted from the substrate fill' or (12 side). Observation of the optical display is performed as a change in .

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a drive control circuit of a liquid crystal display device used to explain the present invention, FIG. 2 is a schematic plan view of an example of a liquid crystal display device according to the present invention, and FIG. 3 is an enlarged view of the main parts 1@ side view,
FIG. 4 is an enlarged sectional view of the main parts of another example of the device of the present invention. ai+ is a substrate, (121 is a transparent substrate, (131 is a liquid crystal,
(241 is the liquid crystal! pole, (29) is the counter electrode, (2η and α stages are the light-shielding electrode and the peripheral electrode opposite to it. Title of the invention: Liquid crystal display device 3, Person making the amendment: Representative Director Norio Ohga6: Number of inventions increased by the amendment: 7° Subject to amendment fl: Detailed explanation of the invention in the specification: 8
, Contents of the amendment (1) In the specification, page 12, line 18, after "to be." It can be composed of a Cr layer or a W layer.A light-shielding electrode (5) is used as a positioning mark at the periphery of the transparent substrate when bonding with the substrate 0υ.
By not forming a light-shielding electrode or a transparent counter electrode (2) near the scribe line of the transparent substrate σ, the contact between these electrodes and the substrate 0υ caused by the scribe can be reduced. It is possible to prevent short circuits between the two.

Claims (1)

[Claims] A semiconductor circuit is provided on the surface of the substrate or on the substrate, a transparent plate is provided opposite to the side of the substrate having the semiconductor circuit, and an opposing portion between the transparent plate and the substrate is maintained liquid-tight, and the liquid A liquid crystal is sealed in a closed space, and a plurality of pixel electrodes for applying voltage to the liquid crystal of the display section and electrodes opposite these are provided on the substrate side and the transparent plate side, and the liquid crystals other than the display section are A liquid crystal display device comprising a light-shielding electrode that provides approximately the same potential and an electrode that opposes the light-shielding electrode on the transparent plate side and the substrate side.